The present invention relates to a process for manufacturing an aperture plate used in a multibeam pattern drawing apparatus including multiple light sources.
Conventionally, photo plotters for drawing accurate patterns (for example, printed substrate circuits) include a laser light source and a deflecting device for scanning the laser light along a main scanning direction onto an object. Usually, the deflecting device is a rotating or oscillating mirror. The object is moved in an auxiliary scanning direction perpendicular to the main scanning direction. A two dimensional pattern is drawn from the main and auxiliary scanning.
However, since the conventional laser photo plotter employs a rotating or a oscillating mirror, the laser beam is scanned along the main scanning direction at a high speed, and it is difficult to increase the accuracy of the beam registration. Furthermore, when a semiconductor laser is used as the laser source, optical components to correct astigmatism and a high speed driving circuit (to accurately modulate the scanning laser beam) are required. Still further, with a semiconductor laser, a large amount of heat is developed.